Starting with a colony, in particular of an inoculum or bacterial suspension, the object of the invention is, on the one hand, to identify bacteria from a set of features measured by photometry and, on the other hand, to carry out growth tests in the presence of an optimum number of antibiotics to demonstrate by nephelometry their action on said bacteria in order to obtain an antibiogram.
To this end, it is worth taking a maximum of measurements with various antibiotics during the same test.
The inoculum is a suspension of bacteria associated with a sample and a patient. It is prepared manually by transfer into an aqueous solution of one or more colonies cultivated in a culture medium in the form of a gel or of elements prepared from urine or from a haemoculture. In fact, after detecting the presence of bacteria, for example by monitoring the variation in the CO.sub.2 above a culture of the sample to be analyzed, the sample to be analyzed is transplanted into a second culture in gel form, this transplantation causing the isolation of a specific type of bacteria to the detriment of others and allowing the obtaining of a monobacterial strain. This strain is then used to produce the inoculum by suspension in an aqueous solution.
Generally speaking, bacteria in suspension in inoculums have relatively reduced virulence owing to the preparation treatment, leading to difficulties in rapid experimentation, the various culturing processes with reagents developing relatively slowly.
Various processes and devices for producing an antibiogram are currently known which use, as a support where the measurements are taken, either individual transparent receivers for receiving bacterial culture (FR-A-2 091 133) or multiple transparent receivers arranged in the form of compartments an plane plates (FR-A-2 449 891, EP-A-0 253 685, DE-A-25 21 025 and US-A-3 942 899).
These processes and devices generally involve displacing the measuring support or supports in front of a source of luminous radiation and measuring the luminous intensity of the beam in one or more directions after it has passed through the receiver or receivers and their content.
The receiver or receivers are supplied with bacterial solution in a known manner, either using manual pipettes or using an automatic pipetting device according to EP-A-0 522 602, the various antibiotics being positioned manually in the various receivers before the filling thereof.
Furthermore, FR-A-2 354 554 describes a tubular compartmental receiver allowing the automatic dispersion of a bacterial culture in various peripheral compartments. These peripheral compartments can each be provided, prior to their supply with bacterial culture, with antibiotics arranged in their bottom in the form of dehydrated reagent.
FR-A-2 280 895 also discloses a fractionation device adapted for use in nephelometry or in photometry and having the form of a disc provided on its periphery with compartments for receiving a reagent in solid form and a bacterial solution, the bacterial solution being transferred from a central chamber to the various compartments by centrifugation.
These various known processes and devices allow photometric and nephelometric measurements to be taken by a series of distinct measurements using distinct containers.
However, these known devices and processes do not allow these measurements to be taken rapidly and successively without manual intervention or with an automatic supply of the measuring supports from a same container while also allowing the implementation of simultaneous operations of identification and antibiogram, even from a low-concentration initial inoculum.